Terminal block assembly for fine wires



Nov. 16, 1965 w. A. REIMER 3,218,604

TERMINAL BLOCK ASSEMBLY FOR FINE WIRES FIG.3

FIG 4 INVENTOR. William A. Reimer ATTY.

N0V 15, 1955 w. A. RElMl-:R 3,218,604

TERMINAL BLOCK ASSEMBLY FOR FINE WIRES Filed April 22, 1963 2Sheets-Sheet 2 FIG.6

F165 INVENTOR.

William A. Reimer ATTY.

United States Patent O 3,218,604 TERB/HNAL BLOCK ASSEMBLY FOR FINE WIRESWiliiam A. Reimer. Villa Parli, Ili., assigner to Automatic ElectricLaboratories, Inc., Northlake, Ill., a corporation o Delaware Filed Apr.22, 1963, Ser. No. 274,555 3 Claims. (Cl. 339-198) This inventionrelates to facilities for terminating wires, especially fine wiresembedded in an encapsulant, and more particularly the invention relatesto terminal blocks for twistor memory units such as for exampledisclosed in copending application Serial No. 194,246 filed May 14,1962, Magnetic Memory System and Manufacture Thereof, by William A.Reimer.

Featured in memory units of the above type are a number of very tinetwistor wires which are placed in an encapsulant made in the form of atwistor tape. The twistor wire envisioned in the invention is describedin A. H. Bodecks article, A New Storage Element for Large- Sized MemoryArrays, The Twistor, Bell System Technical Journal, vol. 36, pp.131941340, November 1957 issue. The tape is normally long and is foldedin successive and alternative folds to form a multiple layer unit.Connected to each end of the tape is a terminal block with the twistorwires terminating therein. However, due to the twistor wires being veryline they are inherently difficult to terminate and consequently fosterhigh assembly cost. Furthermore, the absence of simple andstraightforward means for terminating the twistor wires results in wirebreaking. When the latter occurs substantial cost and effort is requiredto correct the defect due to the fact that the terminating operation isnormally done in the final stages of assembly and after considerabletime is already involved. Moreover, in order to sufliciently isolate theterminating lugs so that the fine wires can be terminated it washeretofore common to arrange the terminals in a fanned-out pattern withrespect to the twistor wires. In other words, the terminals were spacedfurther apart than the individual wires. This pattern required the useof a larger terminal block and resulted in longer lengths of unsupportedwires between the end of the twistor tape and the terminating lugs.

Therefore a principal object of the invention is to provide a terminalblock for a twistor memory unit, for example, whereby the operation ofterminating fine wires to terminals, relative to the prior art, issimplified substantially although made more reliable.

Another object of the invention is to provide a terminal block for atwistor memory unit whereby the length of unsupported twistor wireextending between the end of the tape and the terminal lug is a minimumand free of fanout with respect to the twistor wires.

Still another object of the invention is to provide a terminal designwhich is particularly suited for use in a terminal block of a twistormemory unit.

Still another object of the invention is to provide a terminalarangement wherein the spacing between the individual terminals and thespacing between the individual twistor wires are equal although theterminating lugs are adequately isolated from each other.

A further object of the invention is to provide a terminal blockassembly which can serve as an end plate to the twistor memory unit,giving structural rigidity to the twistor memory unit and simplifyingthe overall assembly operation thereof.

In accordance with these objectives the invention features a terminalthat is U-shaped with one leg thereof serving as the twist-or wire lugand the other the Voutput wire lug. The two lugs are connected by across-leg portion which is of a selective length depending on the ICCparticular terminals position in the arrangement of all the terminals inthe terminal block. Another feature of the invention is that theterminals are arranged in a staggered pattern which enables theindividual terminals to be placed as close together as the individualtwistor wires and with suflicient isolation of the lugs for ease ofterminating the twistor wires and the output wires.

Another feature of the invention is that the individual terminals areembedded in a block of epoxy material which secures them together. Theblock is relatively thin so that the ends of the terminating lugs remainexposed until after the twistor wire terminating operation is complete.Thusly, the epoxy block with the terminals embedded therein constitutesa sub-assembly to the terminal block assembly.

Still another feature of the invention is the potting dam whichsurrounds the terminal block andV is filled with an epoxy material. Thefilled potting dam completely embeds the twistor wire terminating lugsand thereby protects the wires from being damaged.

These and other objects and features of the invention will become moreclearly understood from the following detailed description which makesreference to the accompanying drawings of which:

FIG. 1 is a top view of the terminal block with the individual terminalsplaced in a staggered or offset arrangement.

FIG. 2 is a perspective view of the terminal envisioned for use in theterminal block shown in FIG. 1.

FIG. 3 is a cross sectional view of the terminal block shown in FIG. 1and taken substantially along line 3-3 thereof showing the relativedepth of the epoxy material to that of the exposed portion of theterminal.

FIG. 4 is a perspective View of the terminal block according to theinvention showing the terminals wit-h the twistor wires terminatedthereto.

FIG. 5 is an exploded perspective view of a terminal block assemblyshowing two terminal blocks surrounded by a potting dam on the one sideand a bottom plate Von the other.

FIG. 6 is a side cross sectional view of a terminal block assembly suchas shown in FIG. S and showing the relative depths of epoxy materialafter the potting dam is filled.

Referring now to the drawings, FIG. 1 shows a subassembly 9 whichincludes a molded block 14 made from an epoxy or similar material, and aplurality of terminals 10. The terminals are imbedded in the epoxymaterial in a particular pattern as explained in detail subsequently. Tofacilitate the fabrication of sub-assembly 9 the mold for block 14preferably includes simple locating fingers for locating the terminals10 while the mold is being filled with the epoxy material.

FIG. 2 shows a typical terminal 10 used in block 14. The terminal isU-shaped and is blanked out, for example, from a brass or copper sheet.It includes a twistor wire lug portion 15, an output wire lug portion16, and a cross-leg portion 17. Lug portion 15 is characterized byhaving its end rolled back on itself to form hook 19. On the other hand,lug portion 16 is substantially at and longer than lug portion 15 and ischaracterized by having an aperture 20 near its end for accommodating anoutput wire (not shown). With respect to this element it is to beunderstood that lug 16 is not to be restricted to the configurationshown. The lug could also be without the aperture. Cross-legs 17 bridgethe two lug portions 15 and 16 and vary in length according to thepreferred embodiment, depending on their relative position in thestaggered pattern in block 14. That is, cross-leg 17 is made in threedifferent lengths in order to provide suflicient isolation between thelugs and so that the twistor wires 22, of FIG. 4 for example,

and the output wires can be secured to them without undue difficulty.

In order to simplify the terminating operation the hook portion of theterminals are pre-tinned either individually r in a group after they aremolded in block 14. The tinning operation can be done by dipping onlythe hook 19 in the tin and by virtue of the configuration of the hook acapillary attraction occurs which confines the tin to the hook. Thispre-tinning of the hook aids in terminating the twistor wiressubstantially. This shall be explained in more detail here following.

While according to the embodiment shown terminal has but one lug portion15, it should be understood that a terminal with two of these lugportions can also be used. In this event lug portion 16 would becentered between two oppositely extending lug portions of theconfiguration of lug portion 17. This of course would provide forgreater exibility and capacity to the memory unit.

In order to have a minimum length of unsupported wire between the end ofthe twistor tape and the terminating lug, the terminals are spaced asclose together as the individual twistor wires. Consequently, accordingto the embodiment the twistor wire terminal lugs are arranged in apattern which repeats itself on alternate terminals and the outputterminal lugs 16 are arranged in a pattern which repeats itself everysix terminals. This arrangement is made possible by the terminals 10being of three different lengths and by virtue of the fact that eachterminal is offset or staggered with respect to adjacent terminals. Inconsequence of the arrangement the terminals are as close as the twistorwires while providing adequate spacing between the lugs in order toperform the terminating operation with ease.

From the foregoing it should be apparent that with the particularterminal configuration and the manner in which they are molded in block14 that the operation of terminating the line twistor wires is made lesscomplex and more direct and simple than heretofore was possible.

FIG. 3 illustrates the position of terminals 10 and the effect theaforementioned pattern has insofar as isolating the terminal lugs. Italso shows the relative thickness of block 14 and to what extent theterminals project from the top surface of the epoxy material prior tobeing encompassed by other elements of the terminal block assembly.

FIG. 4 shows tape 21 connected to terminal block 9 with twistor wires 22terminated to hooks 19. The length of unsupported twistor wire dependsupon how much free wire is needed in the terminating operation andwhether the terminals are tanned-out relative to the twistor wires.According to the invention the length of unsupported wire is kept aminimum by virtue of the fact that the terminals are spaced on centersequal to the centers of the individual twistor wires, and once the wiresare free from the tape only an area suicient for a longnose pliers forinstance, is required to terminate them.

It becomes apparent from FIG. 4 how tine wires and in particular thetwistor wires 22 are secured to hooks 19. With hooks 19 pre-tinned, theterminating operation merely involves bringing the wires to the open endof the hook and touching the top surface of the hook with a solder ironin order to bring the tin to a liquid state. Upon reaching this stateand after subsequent cooling the wire becomes fused into the tin.

The tape 21 lies parallel to and against terminal block 14 so that it issupported by it until the terminal block and tape are embedded in afilled potting dam shown in FIG. 6.

FIG. 5 illustrates an end plate or terminal block assembly which has twoterminal blocks 50 and 51 connectable to tapes 54 and 55 respectively, abottom plate 52, and a potting dam 53. The potting dam 53 is fastenedabout the terminal blocks 50 and 51 and to bottom plate 52 by means offastening means (not shown) extending through apertures 40 and 41.Bottom plate 52 can be made from any material which would providestructural rigidity to the memory unit without adding substantially toits weight. The potting darn 53 according to the embodiment is virtuallya frame made of cross pieces having a rectangular-shaped cross-section.The cross pieces are also preferably rigid and light weight. Thematerial from which the cross pieces are made should be compatible withthe material that the potting dam is lled with in Iorder to achieveproper adhesion between the two.

FIG. 6 shows a cross-section of a completed terminal block assembly.Herein, potting dam 53 is placed over tape 54 and 55 and against bottomplate 52. Inside the potting dam is an encapsulant 43, for example anepoxy which completely embeds the terminating lugs 15 while leavingexposed lugs 16. As a result of the tape being formed over the end ofterminal blocks 50 and 51 and covered with either cross pieces 53 orencapsulant 43, any force on tapes 54 and 55 would not extend to thetwistor wires themselves subjecting them to undue stress and evenpossible breakage. Therefore, in effect the assembly provides aself-locking assembly which requires few component parts while making arigid end piece for the memory unit.

The invention has been described in connection with a preferredembodiment, however, this was done merely by Way of example and notintended to impose a limitation to the spirit and scope of my inventionas hereinafter claimed.

What is claimed is:

1. A terminal block assembly for terminating tine wires encapsulated,and extending in parallel with each other, in a flat tape of insulatingmaterial with the bare ends of said wires extending from the end edge ofsaid tape; said assembly comprising: at least one terminal blockcomprising a molded block, and a plurality of terminals embedded in saidmolded block in a staggered pattern eac-h comprising a Iirst lug portionwith one end thereof turned over on itself to form a hook designed tosupport and receive one of said bare wire ends, a second lugr portionformed apart from and parallel to said iirst lug portion, and across-leg portion extending perpendicularly between said rst and seconddug portions with one end there-of joined to the opposite end of saidrst lug portion and the other end thereof joined to the opposite end ofsaid second lug portion; a substantially ilat and rigid plate placedadjacent one surface of said molded block; a rectangular shaped framestructure; connecting means to tix said frame structure to said platewith said tape extending therebetween, said tape being rigidly heldbetween said frame structure and said plate, and an encapsulant formedover at least saidl rst lug portion and within said frame structure.

2. A terminal block assembly for terminating ne wires encapsulated, andextending in parallel with each other in a flat tape of insulatingmaterial with the bare ends of said wires extending from the end edge ofsaid tape; said assembly comprising: a terminal block comprising amolded block of insulating material supporting a portion of said tapeincluding said end edge, and a plurality of terminals embedded in saidmolded block in a predetermined pattern, said terminals having means tosupport and receive said Wires; a substantially at and rigid plateplaced adjacent one surface of said molded block; a rectangular shapedframe structure; connecting means to x said frame structure to saidplate with said tape extending therebetween, said tape being heldrigidly between said frame structure and said plate; and an encapsulantformed over said terminals and said tape and within said framestructure.

3. A terminal bloeiti for terminating fine Wires comprising: a moldedblock; and a plurality of terminals, each comprising; a rst lug portionwith one end thereof turned yover on itself to form a hook which isarranged and constructed to supported and receive one of said wires, asecond lug portion formed apart from and parallel to said first lugportion, and a cross-leg portion extending perpendicularly between saidrst and second lug portions with one end thereof joined to the oppositeend of said first lug portion and the other end thereof joined to theopposite end of said second lug portion, and embedded in said moldedblock such that each of said rst lug portions are otset relative toadjacent first lug portions, and said second lug portions are offsetrelative to adjacent second lug portions.

References Cited by the Applicant UNITED STATES PATENTS JOSEPH D.

Connell et al.

Hecht.

Kershaw 339-242 Korn 339-198 Smith 339-198 Weisberg 339-97 X Obst339-198 Dahlgren 339-103 X Dahlgren et al 339-198 Nieter 339-17 X SEERS,Primary Examiner.

3. A TERMINAL BLOCK FOR TERMINATING FINE WIRES COMPRISING: A MOLDEDBLOCK; AND A PLURALITY OF TERMINALS, EACH COMPRISING; A FIRST LUGPORTION WITH ONE END THEREOF TURNED OVER ON ITSELF TO FORM A HOOK WHICHIS ARRANGED AND CONSTRUCTED TO SUPPORTED AND RECEIVE ONE OF SAID WIRES,A SECOND LUG PORTION FORMED APART FROM AND PARALLEL TO SAID FIRST LUGPORTION, AND A CROSS-LEG PORTION EXTENDING PERPENDICULARLY BETWEEN SAIDFIRST AND SECOND LUG PORTIONS WITH ONE END THEREOF JOINED TO THEOPPOSITE END OF SAID FIRST LUG PORTION AND THE OTHER END THEREOF JOINEDTO THE OPPOSITE END OF SAID SECOND LUG PORTION, AND EMBEDDED IN SAIDMOLDED BLOCK SUCH THAT EACH OF SAID FIRST LUG PORTIONS ARE OFFSETRELATIVE TO ADJACENT FIRST LUG PORTIONS, AND SAID SECOND LUG PORTIONSARE OFFSET RELATIVE TO ADJACENT SECOND LUG PORTIONS.